package com.hmdp.utils;

import cn.hutool.core.lang.UUID;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;

import javax.annotation.Resource;
import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements ILock{
    private String name;
    private StringRedisTemplate stringRedisTemplate;

    public SimpleRedisLock(String name, StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;
    }

    private static final String KEY_PREFIX="lock:";
    private static final String ID_PREFIX= UUID.randomUUID().toString(true)+"-";
    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;
    static {
        UNLOCK_SCRIPT=new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }
    @Override
    public boolean tryLock(long timeoutSec) {
        //获取线程标识  拼接山UUID区分不同的jvm中的线程（在同一个JVM中,每创建一个线程，其ID都是自增的）
        String threadId= ID_PREFIX+Thread.currentThread().getId();
        //获取锁
        Boolean success =
                stringRedisTemplate.opsForValue()
                        .setIfAbsent(KEY_PREFIX+name, threadId, timeoutSec, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(success);
    }

    @Override
    public void unlock() {


        /*
        *
        * 调用lua脚本释放锁*/
        stringRedisTemplate.execute(UNLOCK_SCRIPT,
                Collections.singletonList(KEY_PREFIX+name),
                ID_PREFIX+Thread.currentThread().getId());




//        String threadId= ID_PREFIX+Thread.currentThread().getId();
//        /*
//        * 释放锁的时候要判断锁是不是当前线程的锁
//        * */
//        String redisLock = stringRedisTemplate.opsForValue().get(KEY_PREFIX + name);
//        if (threadId.equals(redisLock)){
//            stringRedisTemplate.delete(KEY_PREFIX+name);
//        }
    }
}
